<?php
class Packt_News_Block_Adminhtml_News_Edit_Form extends Mage_Adminhtml_Block_Widget_Form
{
    protected function _prepareForm()
    {
        $form = new Varien_Data_Form(array(
        'id' => 'edit_form',
        'action' => $this->getUrl('*/*/save', array('id' =>
        $this->getRequest()->getParam('id'))),
        'method' => 'post',
        'enctype' => 'multipart/form-data'
        )
        );
        $form->setUseContainer(true);
        $this->setForm($form);
        return parent::_prepareForm();
    }
}